Dry concentrating-table.



No. 797,239. PATENTED AUG'. l5, 1905. H. MQ SUTTON da W.. L. 61: Gn.STEELE.

DRY CONCENTRATING TABLE..

APPLIOMIQH Hmm MOA, 1902;

i i SHEETS-$113335 1.

- ver" No. 797,239. I PATENTED AUG.. l5, 1905. H. M. SUTTUN L W. L. (Y:E. G. STEELE.

DRY CONGBNTRATING TABLE.

APPLICATION mmm mam, 1992.

No. 797,999. EATENTED A99. 15, 1999. E. M. SUTTON A W. L. E E. E.STEELE.

'DRY GONGENTRATING TABLE.

APPLICATION FILED MUA, 1902.

No. 797,239. PATENTED AUG-.15, 1905.

H. M. SUTTON L W. L. 6a E. G. STEELE.

DRY GONGENTRATING TABLE.

APPLIGATIM Hmm 9120.4, 1902.

. ,fm Afm@ www. a Gummi ccA ,Huvomrnacmw iUNTT'ED STATES PATENT FTTEUE.

HENRY M. SUTTON,

DFH NEN'll'llQATiNlGvffABlhE..

Specification of Letters Patent.

Patented Aug. 15, 1905i.

Application filed December 4, 1902. Serial No. 133,925.

Be it known that we, HENRY M. SUTTON, VALirni-i L. S'rnntn, and EDWIN G.S'rnnnm, citizens of the United States, residing at Dallas, in thecounty of Dallas, cState of Texas, have invented certain new and usefulImprovements in Dry Coneentratiiig-Tables, of which the following is aspecification, reference being had therein to the accompanyingdrawil'igs.

This invention relates to a dry concentrating-table, and particularly toa construction by which a riiiied table is adapted Afor use in dryconcentration by the use of air as a floating medium for the material.

The invention has for an object to `provide a dry concentrating-tableadapted to operate by an air-pressure in a similar manner to an ordinarywet concentratingtablc, said air for Vfloating thc dry material beingpassed upward between the rifiies located upon said surface.

A further object of the invention is to provide a pervionstransverselysinelincd tabletop having longitudinal rifiies thereon andmeans for passing' a current of air through said tcp while the table isreciprocated longitudinally.

Another object of the invention is to provide an improved constructionof parts for supporting the table to permit a longitudinal reciprocationthereof and also adjusting means to vary the transverse inclination ofthe table and the longitudinal inclii'lation thereof.

'Other and further objects and advantages of the invention will behereinafter set forth and the novel features thereof delined by theappended claims.

In the drawings, Figure l is a vertical longitudinal section through thetable; Eig. 2, a side elevation thereof from the back of the table; Fig.3, a vertical cross-section through the table and hopper on line 3 3 ofEig. l; Eig. A, an end view of the driving mechanism; Fig. 5, a detailvertical longitudinal section showing modified means for applying' theair-pressure- Fig. 6 is a vertical cross-secltion on line 6 6 of Fig. 5through this construction of table for producing an intermittentair-blast; Fig. 7, a detail section showing one of the tapering rifiles.Eig. i5 shows Eig. 9 a plan showing the riffles extending the entirelength of the table. Eig. 10 is a similar view showing parallellongitudinal rifdes with advancing terminals, leaving a triangularunriliied space. Fig. 1l is a similar View showing paralleldiagonally-disposed riti'les with advancingterminals and an unrifiledspace above and below the rif-iles. Eig. 12 is a plan showing thetable-top provided with parallel rifiles extending in diiferent planesdown a por tion of thc table to form transverse steps, Fig. 13 is anelevation thereof, showing' this stepped arrangement. Eig. 14: is a planof a further arrangement of rifiles adapted for use with this inventionin which a number of longitudinal steps are provided having parallellongitudinal riilles upon cach one thereof. Fig. .1.5 is an elevation ofthe structure shown in Eig. 14;. Fig. 16 is a plan of a table providedwith parallel riflies alternately extended and formed in separatedsections. Fig. '17 isa plan of the table having rifiies extending fromcorner to corner thereof parallel with the direction of vibration and atright angles to the feed, and Eig. i8 is an elevation of a preferredarrangement of the table-support.

Like letters of reference refer to like parts in the several figures ofthe drawings.

The letter A designates a base or sill of any suitable construction uponwhich an adjusting-frame B is mounted and adapted to carry upon itsupper face the concentratingtable C, above which a feed-hopper D isdisposed at one end and supported by any ,suitable 'form of standards,such as shown at A'. The adjusting-frame B is pivotally mounted at oneend upon the base A by means of the connec# tion B and is provided atits opposite end with a bracket B2, through which the upper end of athreaded adjusting rod or post li" passes, which rod is provided with atraveling nut Bl thereon, having a suitable handle B5 for rotating thesame. The rod B3 is secured at its lower end B to the base, and thetraveling nut upon the rod adjusts one end of the frame B so as to varythe longitudinal inclination of the table. The adjusting-rods aredisposed upon opposite sides of the table at one end thereof, and thetraveling nut B" upop each rod is provided with a sliirocket-wheel l',from which a chain D extends to lthe nut upon the opposite rod.

Upon the adjusting-frame B of the table supports E are disposed andconsist of short rods E', having round-head ends adapted to seat in asocket E2 upon the frame B and a similar socket E3 upon the under faceof the table at one side thereof, while the rod E' at the opposite sideis seated at its upper end in a socket EL upon the under face of thetable and at its lower end in a socket E, carried by an adjusting-screwE6, mounted in a threaded bracket E2, suitably secured to theadjusting'- frame B. This screw is provided with a sprocket-wheel F2,from which a chain E2 eX- tends to the adjuster at the opposite end ofthe frame in order to effect a transverse adjustment of the table. Therods at opposite ends are connected together by a bar El", which causesa simultaneous movement of the bearings in the longitudinal vibration ofthe table.

The table is provided at its upper portion with a series of parallelslats C', extending' longitudinally thereof to provide air-outletsbetween the same. These slats may be of any desired cross-scctiongforinstance, tapering upwardly, as shown in Figs. 3 and 6. Resting upon theslats is a pervious top C2, formed of cloth or any desired materialadapted to permit the passage of air therethrough under pressure, andupon the upper surface of this pervious top a series of ribs or riiiiesG2 is disposed, each of the same being preferably in alinement with theslat C' beneath it and secured thereto in any desired manner. Variousarrangements and characters of rifl'les may be used, as will behereinafter described in connection with the modifications shown in thiscase; but a preferred form `is illustrated in Fig. 7, where the rifHetapers downwardly from the hopper end of the table to the discharge end,as shown at C2. The table is normally inclined transversely of itslength, which inclination maybe adjusted by the meanshereinbeforcdescribed, and a suitable protectingrib (I) is provided atone side and end of the table, while the opposite side is formed with adischarging-ange C andthe discharge end with a similarly-inclined flangeUs. If desired, the slats may be supported between their ends by meansof crossbars C2, as shown in Fig'. l, and any preferred method ofintroducing an air-blast beneath the slats may be used, one form beingshown in Fig. l, wherein a tapering bottom (J2 of airtight character isprovided beneath the slats, and communicating therewith is a feed-pipeF, extending' to a suitable compressing device F', such as a fan, andhaving abovefits discharge a bafHe-plate F2 to prevent a direct pressurethrough the table above the discharge from the pipe. This pipe may be ofa iiexible character adjacent to its connection with the table, as shownat F2, so as to permita vibration of the table without affecting therelation of the pipe thereto.

The tapering bottom C of the air-chamber i i i i varies the capacity orarea thereof at the ends, so as to maintain an equal pressure of air atall points, and also provides means for conducting the tine dust whichmay pass through the pervious top to a central point, where it may beremoved whenever necessary.

For the purpose of imparting a longitudinal reciprocation or vibrationto the table a bracket G is secured to the under side at the hopper endthereof and a pitman-rod G' pivotally secured at one end to said bracketand at its opposite end to an adjustable connecting-sleeve G2, havingits free end pivotally connected to a crank-arm G3, having' its shaft G4mounted in a bearing G5 upon the base of the machine. For the purpose ofproviding a vertical adjustment of the pivoted end of theconnecting-sleeve G2, and thus regulating the extent of throw orvibration of the table, an adjusting-screw GG is mounted in the verticalmember of the crank-arm and provided at its lower end with a handle G7,while the free end of the connecting-sleeve is pivotally secured to atraveling nut G2 by the pivot-pin G". The horiZontally-disposed end G10of the crank-arm is provided with an antifrictionroller Gu, disposedbeneath an operating-cam H, mounted upon a shaft H', suitably journaledat its opposite ends in standards H2. rThis shaft is provided with acone drivingpulley H, connected by the belt H'i with a similaroppositely-disposed cone-pulley upon the shaft .f 6, also journaled atits opposite ends in the standards H2. The shaft H is provided at oneend with the driving-pulley H7, connected to any suitable source ofpower, and at its opposite end with a similar pulley Hs, connected by abelt H(J with a drivingpulley H12 upon the end of the shaft D', carryingthe feed-roller D2 beneath the hopper. For the purpose of adjusting thebelt H* upon the cone-pulleys for regulating the driving speed of theseveral. parts a belt-shifter I is provided comprising a screw-shaft l',mounted in a bearing I2 u on one standard and )rovided with a loop 12,surrounding the belt, while the free end of the shaft is guided in itsmovement by means of a supporting-rod lf, carried bythe oppositestandards, upon which a collar I is adapted to slide. The reciprocatingmechanism for the table is held under proper tension by means of aspring J, extending froni the bracket G to a fixed support J', carriedupon the frame B and provided with a connecting-rod J2, having athreaded adjusting-screw J3 mounted in the xed support J' and providedwith a hand-wheel J4 for adjusting the tension of the spring to hold thecrank-arm in contact with its operating-cam and for restoring the tableafter its movement' by said cam.

The shaft D' of the feed-roller D2 beneath the hopper D is mounted atits opposite ends in bearings A2, carried upon the standards A', and forthe purpose of disconnecting this feedroller from its driving mechanismwhenever desired a clutch D3 is slidably keyed upon the shaft D andprovided with a handle D", pivoted thereto at D" and pivoted at itslower end in a iixed arm D, extending from one of the bearings A3. TheYfeed-roller Dil is provided with a series of longitudinal recesses orcorrugations Dl, which may be of any desired depth or area, depending`upon the feed desired upon the table, and the roller is disposed beneaththe opening at the bottom of the hopper. At one side of this opening aflexible strip B8 is disposed to prevent escape of material at the rearof the roller, and uponr the front of the hopper an adjustable dischargegate D" is slidingly mounted and adapted to be adjusted by a hand-wheelDm, threaded upon the upper end Dlof the operating-rod Vfor the gate anddisposed between the arms of the bracket D, as shown in Fig. 3.

ln Figs. 1 and 2 the table-supports l are shown as disposed in avertical plane extending through the 'frame l) and the table (Il, theresult of which causes the table to reciprocate longitudinally and alsoto descend toward a lower parallel horizontal plane in its movement awayfrom the hopper. VIt has been found very desirable, and preferable inmany cases, to incline the supports toward the head or feed end of thetable, so that the table rises into a parallel horizontal plane at eachforward stroke and returns to the initial plane upon the return stroke.ln Fig. l an arrangement of the parts Yfor accomplishing this object isshown, wherein the supports'E are inclined obliquely to a vertical planethrough the table and frame and toward the feed end of the table. lt hasalso been found preferable in many cases to provide an equal Yforwardand return movement instead of the quick forward and slow return securedby the cam H in Figs. l and 2 and the springd coiperating therewith. .inorder to secure this equal movement, an eccentric U may be secured uponthe-driving-shaft H and surrounded by a strap O', having' a dependingarm U2, pivotally connected at its lower end O3 to the crank-arm G bymeans of the free arm Uw thereof, while the weight of the table isbalanced by a spring J, connected to a support J, similar to that shownin Fig-1. The cranlcarm G is similar in construction to that heretoforedescribed, as are the other parts of the table and support, the onlydifferences in construction and arrangement being the diagonaldisposition of the supports E and the eccentric connection, whereby thetable vibrates backward and forward. longitudinally and is givensimultaneously a rising-and-falling movementin a vertical plane. i

The form of air-supply shown in Fig. 1 provides for a constant pressure;but the in- Vention is equally applicable :for use in connection with auintermittent pressure, and for this purpose any desired form of airblastmay be used, for instance, as shown in Figs. 5 and 6. The table C may beprovided beneath the slats C with an apertured partition K, the opening'therein extending' longitudinally of the table and being provided withupwardlymovable valve-plates K toadmit the passage of air into thechamber beneath the slats and pervious top C, while beneath thispartition l( the perforated bottom. plate li of the bellows is disposedand provided with the movable section K, flexibly connected at K" withthe stationary portion ofthe bottom. This movable portion K is providedwith transverse openings K, having 'valves li above the same andprovided upon its under surface with the pivoting-bracket K7, connectedto any suitable driving mechanismfor instance, a crank-arm L, similar tothat shown in connection with the driving mechanism the horizontalmember L of which is connected by a rod L with `the bracket Kvwhile thevertical member is provided with a sleeve L, mounted thereon forlongitudinal adjustment. This sleeve is adjustably connected to a pitmanL, extending to a boxing L, disposed about a cam L, located upon thedriving-shaft lrl/ of the mechanism hereinbefore described. Yln thisVform of table, whereon the ore is `floated or suspended bythe airpassing upward through the pervious top, any desired form or arrangementof riliies may be used, and `for the purpose of showing theapplicability of a number of Yforms now in use upon washers which areadapted to be disposed upon the pervious table herein used we haveillustrated in Fig. 8 a series of longitudinal riiiies M of equal lengthextending parallel toward the foot of the table and terniinating so asto leave a rectangular unrifiled space NP. lin Fig. 9 a similararrangement of ril'lles M2 is shown extending the entire length of thetable.

Fig. YLO shows the longitudinal riilics M with advancing terminals,leaving a triangular unril'i'yled space M", while Fig. ll shows theriii'les lvl disposed diagonally to the sides of the table withadvancing' terminals, leaving an unril'lled space M above and. below theriliies and also at one end thereof.

Fig. 12 illustrates a form of table having steps MT extendingtransversely in different horizontal planes, the rii'lles his beingdisposed longitudinally of the table and the unrified space M" providedupon the lowest step. The tendency of the gang-ue in the movement of thetable when operating upon very fine material is to Yliow back toward thehead of the table, and the stepped arrangement (shown in Fig. 13)prevents this objection.

Fig. 14 is a top plan of a table provided with a number of longitudinalsteps N, having' parallel longitudinal riiles N thereon, and for thepurpose of allowing the material to be returned toward the head of thetable as it passes from one level to the next below the usual chutes orgutters h are provided, as shown in Fig. 15.

In Fig. 16 a table is shown having riifles N3 in separated portions, thealternate riiiies terminating at different lengths, while an unriiiiedportion i 4 is provided at one end ofthe table.

In Fig. I7 the riffles N5 extend entirely across the table from onecorner to the other, while the vibrations of the table arein line withthe riflies and the feed at a right angle thereto.

As before stated, the invention is not conlined to the use of any one ofthe forms herein shown, they being illustrated for the purpose ofdemonstrating the adaptability of the table to the differentarrangements of the riflies now in use in various forms ofconcentrators.

The table C is inclined transversely and also longitudinally, the footor discharge end being slightly higher than the feed or hopper end, thuscausing the material to travel upwardly thereon in its movement towardthe discharge end of the table. This is essential when operating uponfine ores in order to retard the too rapid travel of the values whichwould otherwise occur. In other characters of ores and those of largersize mesh itmay be desirable that the table be perfectly flatlongitudinally or even slightly lower at the foot end, and the adjustingmeans applied to the frame for varying the longitudinal inclination ofthe table is to adapt the same for use with diiferent sizes and gradesof ore. The vibrating means for the table herein shown cause the same tobe drawn back slowly and returned forward quickly by the tension of thespring; but, if desired, this movement can be completely reversed and anupward or lifting movement may be given the table, if preferred, byadjusting the supports to slope the table toward the head or hopper endthereof. If it be desired to drop the table slightly at each forwardstroke, the supports are given a slight inclination toward the foot ordischarge end of the table, as shown in Fig. 18, While the length ofstroke or travel of the table is adjustable by the hand-wheel and screwoperating in the vertical arm of the crank-lever, as shown. The form ofthis vibrating mechanism herein disclosed is merely intended toillustrate a desirable construction; but the invention is notspecifically confined thereto. The ore or material to be concentrated isfed by the roller beneath the hopper upon the head end of the table inpredetermined quantities and falls between the tapering riifles upon theupper surface of the pervious top of the table. The air passing' upwardthrough this top stratifies the different minerals, while thelongitudinal vibration in connection with the inclination of the tableretains this stratification so as to discharge the different results ofthe concentration at different points upon the table.

The present invention provides a dry concentrator adapted to treat oresin a similar manner to the wet tables heretofore used and to secure amuch more efhcient and rapid operation with a minimum loss of the valuesin the tailings which pass from the table. rIhe separating medium usedto float or support the ore being air adapts the invention for use inthemany mining localities where water is often entirely absent, thusrendering a wet separation impracticable and avoiding the necessity oftransporting the ore, frequently at a great cost, to a mill orseparating plant at a distance from the mine. Furthermore, very oftenthe ores carry matter soluble in water, which either prevents aseparation being effected by thickening the pulp, and thus iioating outthe values, or the values themselves may be soluble, or partially so,and thus pass over the table in solution. Nothing in ores being solublein air, it will be apparent that the formation of such a pulp orthickening of a solution which occurs in wet separation is entirelyavoided. An ore may carry a value very soft as compared to the gangue orother values, which results in this value being slimed in crushing andfloated on the surface of the water. Under certain conditions ores willslime to such an extent as to be impossible of commercial treatment byany wet method, either mechanical or chemical. In the present table anysize mesh of material can be treated, however iine. The finer or morepacky the material the better results are obtained when a constantpressure of air is used. In the use of water flowing over a table thereis a tendency to mix the values and cause loss by washing them off thetable. As the water flows over the table it causes eddies and whirls,each disturbing the stratilications on the table, and as the clear wateriiows over the clean-up space at the lower end it washes down the stratatoward the discharge side, causing them to overlap, with the result thata large portion of the concentrates must bereturned for a furthertreatment. This water also washes the values which have a tendency tocome out high up on the table down toward the discharge side, causingthe values to pass off the table within a few inches of the gangue ordross, and considerable loss results from this cause. By introducing theseparating medium or air through the pervious table-top there is nowhirling or eddying of the ore, which is simply rested or floated on acushion of air suiiiciently strong to float the gangue, but not strongenough to blow the mass about. The ore being iioated, the motion of thetable causes the values to settle to the bottom and stratify, theparticles having the greatest speciiic gravity lying upon the bottomagainst one varese or more of the rifffes. After the stratification ofthe ore has been effected there is nothing to disturb this, and the massfiows downward toward the foot end of the table, while the particlesreach a portion of the sloping or tapering riffles low enough to allowthem to pass over and to arrange themselves in well -delined zones,according to their specific gravity. It will be readily seen that thereis nothing' to disturb these zones as they travel across the clean-up orunriffled space at the foot of the table, so that a perfect separationis effected whereby the heaviest and most valuable values will passofi'l the table high up on the feed side and away from the gangue orstrata of lesser specific gravity and value. Attention is also called tothe fact that the use of air, being a much lighter medium than water,causes the particles of ore being separated to have a greater effectiveweight in a lighter medium than a heavier. A particle of mineral whensuspended in water displaces a greater weight thereof than of air, andthe apparent weight of the mineral is less than when in air, so that thedifference in effective weight between the mineral and gangue isconsiderablyless when immersed in water than when in air, thus making itpossible to separate particles of nearer the same specific gravity inair than in water. Also the natural cohesive force is the same in wateras in air, and with the lessened effective weight in water between theparticles the more difficult it is for the water to break this cohesiveeffect and separate the values from the gangue, while the action may bereadily accomplished in the air-separating medium. This use of air alsopermits the use of the invention in very cold climates, as there is nomedium used in the concentration which could freeze and interfere withthe action of the device. Another serious defect experienced in wetconcentrating-tables having a blank or un'riff'led space at the foot endis when the ore mass reaches this space, it is greatly reduced in bulk,passing' over the same in a very thin layer, and in order not to washthis layer of thin material down into the waste material the water mustbe handled very carefully and must `fiow very evenly over the ore. Thisis very difficult to accomplish, and as the result the water frequentlydoes not cover the entire layer of ore, but runs in streams and streaksacross the table, changing its course when obstructed by a mass of oreor by a change in the feed or water supply. The portions of ore leftuncovered by the wash-water quickly dry and are floated away when nextbrought in contact with the water, as it .is almost impossible to sinkvery line dry ore in water. In dry ore-concentrators it has heretoforebeen very difficult to effect a very satisfactory separation, as noefficient means have been provided to secure a stratification of themass and the subsequent separation of the strata.

Among the important features by which the efficient action of thepresent invention is secured and the difficulties in the prior artobviated is the pervious top through which the air passes to cause theore to stratify, the riflies upon said top by which the gradualseparation of the strata can be effected, and the longitudinal vibrationwhich causes the material to travel from the head to the foot of thetable.

A further important feature is the use of the tapering' riflles upon adry concentratingtable having a pervious top, said riffles being eitherof advancing terminals or otherwise arranged. lt will therefore beobvious that changes may be made in the details of construction andconfiguration without departing` from the spirit of the invention asdefined by the appended claims.

lffaving described our invention and set forth its merits, whatwe claim,and desire to secure by Letters Patent, isw

l. The combination of an inclined pervious 'fioor having its surfaceprovided with longitudinally-disposed riffies, means for maintainingsuccessive zones of separated material, and means for maintainingbeneath the floor a uniform upward pressure of air through the perviousfioor and the material upon it.

2. f lhe combination of an inclined pervious fioor having' its surfaceprovided with rifiies and an unrifiied plain space at their dischargeends, and means for maintaining beneath the floor a uniform upwardpressure of air through the pervious floor and the material upon it.

3. rlhe combination of a pervious inclined fioor having its surfaceprovided with longitudinally-disposed riffles, means for maintaining anupward pressure of air through the pervious floor, means for causing thespread and travel over it of granular or pulverulent material, and meansfor maintaining a stratification of the particles and for causing saidstrata to emerge beyond the mass as successive zones and for maintainingthe graduation of the particles at the delivery portion of the floor.

4. The combination of a pervious floor having part of its surfacedivided into longitudinal channels, i'neans foiI causing the spread andtravel over it of granular or pulverulent material, means formaintaining a stratification of the particles and for causing said.strata to emerge beyond the mass and channeled surface as successiveZones and for maintaining said zones, and means for maintaining anupward pressure of air through the pervious floor and the material uponit.

ln a dry concentrator, the combination of a pervious inclined floorprovided upon its upper surface with longitudinal riffles and asubstantially unriffled portion, with means for maintaining an upwarduniform pressure of air through the pervious floor and thematerialthereon, and means for feeding saidV material relative to said riffles.

6. In a dry concentrator, the combination of a pervious inclined floorprovided upon its upper surface with longitudinal riifles and aSubstantially unrilfled portion, with means for maintaining an upwarduniform pressure of air through the pervious `floor and the materialthereon, and means for longitudinally vibrating said floor substantiallyparallel to the riflies thereon.

7. In a dry concentrator, the combination of a pervious inclined floorprovided upon its upper surface with longitudinal rifiles and asubstantially unrifiied portion, with means for maintaining an upwarduniform pressure of air through the pervious floor and the materialthereon, means for longitudinally vibrating said door substantiallyparallel to the riffies thereon, means for adjusting the transverseinclination of said floor, and means for longitudinally inclining saidfloor.

8. In a dry concentrating-table, a pervious floor, means formaintaining` an upward pressure of air through said iioor and thematerial thereon,rifles extending longitudinally of said floor anddiminishing in height toward the discharge end thereof where theyterminate at different distances relative to a line transversely of thefloor, and means for producing a feed of material upon said table.

9. In a dry concentrating-table, a pervious floor, means for maintainingan upward pressure of air through saidfloor and the material thereon,rifiies extending' longitudinally of said floor and diminishing inheight toward thc discharge end thereof where they terminate at dierentdistances relative to a linc transversely of the floor, and means forlongitudinally vibrating said iioor.

l0. In a dry concentrating-table, a riflied pervious floor, means forfeeding material upon said table, means for maintaining an upwardpressure of air through said fioor and the material thereon, anair-chamber beneath said floor having a bottom inclined upwardly towardeach end of the table, and an air connection disposed centrally of saidbottom.

ll. The combination of an inclined pervious floor having its surfaceprovided with longitudinal riflles and means for maintaining' zones ofseparated material at the delivery ends thereof, means for maintainingan upward pressure of air through the pervious ioor and the materialupon it, and an oscillating snpport for said Hoor to permit the risingand descending movement in the vibration thereof.

12. The combination of an inclined pervious floor having' its surfaceprovided with longitu dinal rifiics and means for maintaining' zones ofseparated material at the delivery ends thereof, means for maintainingan upward pressure of air through the pervious floor and the materialupon it, and an oscillating' support for said floor constructed andarranged to produce a rising' movement thereof during the forward stroketoward the discharge end and a descending movement in the return stroketoward the feed end thereof.

13. The combination of an inclined pervious iioor having its surfaceprovided with longitudinal rifiles and means for maintaining zones ofseparated material at the delivery ends thereof, means for maintainingan ugward pressure of air through the pervious floor and the materialupon it, a frame beneath said licor, a supporting member having' apivot-al hearing' in said frame and floor and disposed obliquely towardthe feed end of the table, and means for imparting' a reciprocatorymovement to said table.

In testimony whereof we afiX our signatures in presence of twowitnesses.

HENRY M. SUTON.

IV ALTER L. STEELE.

EDIVIN G. STEELE.

IVitn ess es:

OLIvER V. STEELE, JAMES F. DAvIEs.

